WO2025174359A1

WO2025174359A1 - Machine-direction-oriented, post-consumer recyclate-based film resin

Info

Publication number: WO2025174359A1
Application number: PCT/US2024/015531
Authority: WO
Inventors: Kenneth E. Klaber
Original assignee: Equistar Chemicals LP
Current assignee: Equistar Chemicals LP
Priority date: 2024-02-13
Filing date: 2024-02-13
Publication date: 2025-08-21
Anticipated expiration: 2026-08-13

Abstract

A method for recycling plastic waste including the steps of (i) grinding plastic waste selected from the group consisting of post-consumer recyclate and post-industrial recyclate, thereby providing particles; (ii) determining the particles' viscosity, molecular weight distribution, and melt index; and (iii) melt blending the particles with a high molecular weight, high density polyethylene having a melt index of 0.008 to 1.0 g/10 min, thereby yielding a machine-direction-oriented, PCR-based film resin.

Description

MACHINE-DIRECTION-ORIENTED, POST-CONSUMER RECYCLATE-BASED

FILM RESIN

FIELD OF THE INVENTION

[0001] In general, the present disclosure relates to the field of chemistry. More specifically, the present disclosure relates to post-consumer recyclate. In particular, the present disclosure relates to preparing a machine-direction-oriented, PCR-based film resin, related processes, and products prepared therefrom.

BACKGROUND OF THE INVENTION

[0002] The downside to the demand for polyolefin plastics is an increase in plastic waste. As such, there is considerable interest in developing methods to recycle plastic waste. In addition to reducing the amount of plastic waste, other benefits of recycling plastic waste include reducing carbon footprint, consuming less energy, improving water consumption, and using less raw materials.

[0003] In many instances, before plastic waste is recycled and turned into usable resin, the plastic materials are gathered and sent through a process to produce plastic resin pellets. In some instances, the plastics recycling system is a mechanical recycling system, including the steps of sorting, cleaning, shredding, melting, and remolding.

[0004] In some instances, the resulting plastic resin pellets are made from or containing polyolefins, non-polyolefmic polymers, and other contaminants. In some instances, the non- polyolefinic polymers or the other contaminants are present in an amount that adversely affects the properties of the plastic resin pellets. In some instances, the non-polyolefmic polymers or the other contaminants provide stress points in articles made from or containing the plastic resin pellets.

BRIEF SUMMARY OF THE INVENTION

[0005] In a general embodiment, the present disclosure provides a method for recycling plastic waste including the steps of (i) grinding plastic waste, wherein the plastic waste is selected from the group consisting of post-consumer recyclate and post-industrial recyclate, thereby providing particles having dimensions smaller than 1000 microns; (ii) characterizing the particles, thereby determining the particles’ (a) viscosity at a shear rate of 0.025 radians/second, (b) viscosity at a shear rate of 100 radians/second, (c) molecular weight distribution, and (d) melt index at 190 degrees Celsius under 2.16 kg force; and (iii) melt blending (a) a first amount of the particles with (b) a second amount of a high molecular weight, high density polyethylene having a melt index of 0.008 to 1 .0 g/10 min, thereby yielding a machine-direction-oriented, PCR-based film resin having (I) a viscosity at a shear rate of 0.025 radians/second of 8.0*10⁴ to 1.2*10⁵ poise, (II) a viscosity at a shear rate of 100 radians/second of 8.8* 10³ to 5.5xl0³ poise, (III) a weight averaged molecular weight/number averaged molecular weight (M_w/M_n) > 4, and (IV) melt index at 190 degrees Celsius under 2.16 kg of 0.05 to 4 g/10 min.

|0006| In some embodiments, the present disclosure provides a post-consumer recycled resin prepared from a post-consumer recyclate, wherein the resin is selected from the group consisting of polyethylene and polypropylene. In some embodiments, the polyethylene is a high- density polyethylene.

[0007] In some embodiments, the present disclosure provides a post-industrial recycled resin prepared from a post-industrial recyclate, wherein the resin is selected from the group consisting of polyethylene and polypropylene. In some embodiments, the polyethylene is a high- density polyethylene.

[0008] In some embodiments, the present disclosure provides a polymer composition made from or containing resin selected from the group consisting of a post-consumer recycled resin and a post-industrial recycled resin.

[0009] In some embodiments, the present disclosure provides an article of manufacture made from or containing a resin selected from the group consisting of post-consumer recycled resins and post-industrial recycled resins.

[0010] While multiple embodiments are disclosed, still other embodiments will become apparent to those skilled in the art from the following detailed description. As will be apparent, certain embodiments, as disclosed herein, are capable of modifications in various aspects, without departing from the spirit and scope of the claims as presented herein. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not restrictive.

DETAILED DESCRIPTION OF THE INVENTION

[0011] While the provided embodiments will be described more fully hereinafter, these embodiments are provided to satisfy applicable laws and regulations. As such, it will be apparent to those skilled in the art that the embodiments can incorporate changes and modifications without departing from the general scope. This disclosure is intended to include the modifications and alterations in so far as the modifications and alterations come within the scope of the appended claims or the equivalents thereof. |0012] As used in this specification and the claims, the singular forms “a,” “an,” and “the” include plural referents unless the context dictates otherwise.

[0013] As used in this specification and the claims, the terms “comprising,” “containing,” or “including” refer to the presence of that at least the named compound, element, material, particle, or method step in the composition, the article, or the method, but does not exclude the presence of other compounds, elements, materials, particles, or method steps even if the other such compounds, elements, materials, particles, or method steps have the same function as that which is named, unless expressly excluded in the claims. It is also to be understood that the mention of one or more method steps does not preclude the presence of additional method steps before or after the combined recited steps or intervening method steps between those steps expressly identified.

[0014] Moreover, it is also to be understood that the lettering of process steps or ingredients is for identifying discrete activities or ingredients and the recited lettering can be arranged in any sequence, unless expressly indicated.

[0015] For the purpose of the present description and of the claims which follow, except where otherwise indicated, numbers expressing amounts, quantities, percentages, and so forth, are to be understood as being modified by the term “about”. Also, ranges include any combination of the maximum and minimum points disclosed and include any intermediate ranges therein, which may or may not be specifically enumerated herein.

[0016] Definitions

[0017] In the present description, the term “additive composition” refers to a composition made from or containing an additive.

[0018] In the present description, the term “a-olefin” or “alpha-olefin” refers to an olefin of formula CH2=CH — R, wherein R is a linear or branched alkyl containing from 1 to 10 carbon atoms. In some embodiments, the a-olefin is selected from the group consisting of propylene, 1- butene, 1 -pentene, 1 -hexene, 1 -octene, and 1 -decene.

[0019] In the present description, the terms “comminute,” “grind,” “mill,” “powder,” “pulverize,” and “triturate” are used interchangeably and refer to dividing or reducing postconsumer polymer-containing waste or post-industrial polymer-containing waste mechanically into particles having dimensions smaller than 1mm (or 1000 microns), alternatively smaller than 100 microns, alternatively smaller than 10 microns, alternatively smaller than 1 micron, alternatively in the range of 10 microns to 1000 microns, alternatively 10 microns to 100 microns. |0020| In the present description, the term “contaminant” refers to any chemical substance present in a post-consumer recyclate (PCR), a post-industrial recyclate (PIR), a post-consumer recycled resin (PCR resin), or a post-industrial recycled resin (PIR resin), wherein the PCR, the PIR, the PCR resin, or the PIR resin is made from or containing a selected polymer and the presence of the chemical substance thereby renders the PCR, the PIR, the PCR resin, or the PIR resin compositionally different from the pure, selected polymer. In some embodiments, the contaminant is present in an amount ranging from parts per billion (ppb) to percentages, based upon the total weight of the PCR, the PIR, the PCR resin, or the PIR resin. In some embodiments, a multiplicity of contaminants is present. In some embodiments, the contaminant is selected from the group consisting of acrylonitrile butadiene styrene (ABS), calcium carbonate, coffee grounds, diapers, dirt, fillers, food stuffs, glass, grass, labels, metals (including aluminum), nylon, other inorganics, other polymers, paper, plant stems, polycarbonates, polyethylene terephthalate (PET), processing additives, property-imparting additives, rubbers, and wood.

[0021] In the present description, the term “dX value,” where X is 50 or 90, refers to the measured particle diameter upper limit for particles falling within the bottom 50% or 90% by mass, respectively, of the particle distribution. For example, a d50 value of 0.3 pm refers to 50% of the particles in the distribution by mass have a diameter of greater than 0.3 pm and 50% of the particles by mass have a diameter lower than 0.3 pm. The d50 value is also referred to as the median particle size herein.

[0022] In the present description, the term “elastomer” refers to polymer compounds having rubber-like properties and crystallinity in the range of from about 0 percent to about 20 percent.

[0023] In the present description, the term “first” refers to the order in which a particular species is presented and does not necessarily indicate that a “second” species will be presented. For example, “first polymer composition” refers to the first of at least one polymer composition. The term does not reflect priority, importance, or significance in any other way. Similar terms used that can be used herein include “second,” “third,” “fourth,” etc.

[0024] In the present description, the term “high density polyethylene” (HDPE) refers to a polyethylene having a density range of 0.941 to 0.970 g/cm³, alternatively about 0.946 to about 0.968 g/cm³.

[0025] In the present description, the term “high molecular weight” refers to a molecular weight range, both weight average and number average molecular weight, of 1.3 to 2.9 million, alternatively 1.5 to 2.5 million. |0026| In the present description, the term “homopolymer” refers to polymers derived from a single monomeric unit. To the extent that a homopolymer is derived from more than a single monomeric unit, the incorporation of additional monomeric units has no measurable effect on the polymer’s primary, secondary or tertiary structure or no effect on the polymer’s physical or chemical properties. In other words, there is no measurable difference between a polymer, comprising 100 weight percent of a first monomeric unit, and a copolymer, including more than a single monomeric unit.

[0027] In the present description, the term “International Code Council (ICC) Certification” refers to products certified as using 100% post consumer resins.

[0028] In the present description, the term “interpolymer” refers to a polymer prepared by the polymerization of at least two types of monomers or comonomers. The term “interpolymer” includes copolymers, terpolymers, tetrapolymers, and the like. In some embodiments, the term “copolymer” refers to polymers prepared from two different types of monomers or comonomers. In some embodiments, the term “terpolymer” refers to polymers prepared from three different types of monomers or comonomers. In some embodiments, the term “tetrapolymer” refers to polymers prepared from four different types of monomers or comonomers. In some embodiments, the term “copolymer” is used interchangeably with “interpolymer” and refers to polymers made from three or more different types of monomers or comonomers.

[0029] In the present description, the terms “monomer” and “comonomer” are used interchangeably. The terms refer to any compound with a polymerizable moiety that is added to a reactor to produce a polymer. In those instances wherein a polymer is described as made from or containing one or more monomers, for example, a polymer made from or containing propylene and ethylene, the polymer, of course, is made from or containing units derived from the monomers, for example, — CFh — CH2 — , and not the monomer itself, for example, CH2=CH2.

[0030] In the present description, the term “PCR” refers interchangeably to Post-Consumer

Recycled or Post-Consumer Recyclate, including polymers such as high-density polyethylene (HDPE) and polypropylene (PP), which are recycled and reprocessed into a resin for use in various applications.

[0031] In the present description, the term “PIR” refers interchangeably to Post-Industrial Recycled or Post-Industrial Recyclate.

[0032] In the present description, the term “polymer” refers to a macromolecular compound prepared by polymerizing monomers of the same or different type. The term “polymer” includes homopolymers, copolymers, terpolymers, interpolymers, and so on. |0033| In the present description, the term “polymer composition” refers to a composition made from or containing a polymer.

[0034] In the present description, the term “polyolefin” is used herein broadly and refers to polymers such as polyethylene, ethylene-alpha olefin copolymers (EAO), polypropylene, polybutene, and ethylene copolymers having at least about 50 percent by weight of ethylene polymerized with a lesser amount of a comonomer such as vinyl acetate, and other polymeric resins within the "olefin" family classification.

[0035] In some instances, polyolefins are made by a variety of processes including batch and continuous processes using single, staged, or sequential reactors, slurry, solution, and fluidized bed processes and one or more catalysts including for example, heterogeneous and homogeneous systems and Ziegler, Phillips, metallocene, single-site, and constrained geometry catalysts to produce polymers having different combinations of properties.

[0036] In the present description, the term “post consumer recycled (PCR) resin” refers to the recycled product of waste created by consumers, including high-density polyethylene postconsumer recycled resin (HDPE PCR) and polypropylene post-consumer recycled resin (PP PCR). Among other forms, PCR resins may take the form of granules, pellets, and powders.

[0037] In the present description, the term “post industrial recycled (PIR) resin” refers to the recycled product of waste generated by manufacturers during the preparation of polymer-based products. In the present description, the disclosed, recycling processes for preparing and using PCR resins are extendable to PIR resins.

[0038] In the present description, the term “recycle” refers to the conversion of waste into a reusable material. The waste is created by consumers, in the case of post-consumer waste, or by manufacturers during the preparation of polymer-based products, in the case of post-industrial waste.

[0039] In the present description, the term “room temperature” refers to a temperature of about 25 degrees Celsius.

[0040] In the present description, the term “thermoplastic polymer” refers to a polymer that softens when exposed to heat and returns to its original condition when cooled to room temperature.

[0041] In the present description, the term “virgin polymers” refers to polymers prepared in polymerization processes from monomers, with or without catalysts or processing aids, and which are yet to be manufactured into first-use consumer or industrial products. [00421 Testing

[0043] ASTM D 792 is entitled “Test Methods for Density and Specific Gravity (Relative Density) of Plastics by Displacement.” The term “ASTM D 792” as used herein refers to the standard test method for determining the specific gravity (relative density) and density of solid plastics in forms such as sheets, rods, tubes, or molded items. The test method includes determining the mass of a specimen of the solid plastic in air, determining the apparent mass of the specimen upon immersion in a liquid, and calculating the specimen’s specific gravity (relative density).

[0044] ASTM D 1238 is entitled “Test Method for Melt Flow Rates of Thermoplastics by Extrusion Plastometer.” The term “ASTM D 1238” as used herein refers to a test method covering the determination of the rate of extrusion of molten thermoplastic resins using an extrusion plastometer. After a specified preheating time, resin is extruded through a die with a specified length and orifice diameter under prescribed conditions of temperature, load, and piston position in the barrel.

[0045] Throughout the present description and claims, the standard melt index values of polyethylene polymers are measured according to ASTM D 1238, using a piston load of 2.16 kg and at a temperature of 190 degrees Celsius. The High Load Melt Index (or HLMI) values are also measured according to ASTM D 1238, but using a piston load of 21.6 kg and at a temperature of 190 degrees Celsius.

[0046] Throughout the present description and claims, the standard melt flow rate values of polypropylene polymers are measured according to ASTM D 1238, using a piston load of 2.16 kg and at a temperature of 230 degrees Celsius.

[0047] ASTM D 1505 is entitled “Standard Test Method for Density of Plastics by the Density-Gradient Technique.” The temi “ASTM D 1505” as used herein refers to a test method based on observing the level to which a test specimen sinks in a liquid column exhibiting a density gradient, in comparison with standards.

[0048] For the referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org.

[0049] In a general embodiment, the present disclosure provides a method for recycling plastic waste including the steps of (i) grinding plastic waste, wherein the plastic waste is selected from the group consisting of post-consumer recyclate and post-industrial recyclate, thereby providing particles having dimensions smaller than 1000 microns; (ii) characterizing the particles, thereby determining the particles’ (a) viscosity at a shear rate of 0.025 radians/second, (b) viscosity at a shear rate of 100 radians/second, (c) molecular weight distribution, and (d) melt index at 190 degrees Celsius under 2.16 kg force; and (iii) melt blending (a) a first amount of the particles with

(b) a second amount of a high molecular weight, high density polyethylene having a melt index of 0.008 to 1.0 g/ 10 min, thereby yielding a machine-direction-oriented, PCR-based film resin having (I) a viscosity at a shear rate of 0.025 radians/second of 8.0*10⁴ to 1.2*10⁵ poise, (II) a viscosity at a shear rate of 100 radians/second of 8.8*10³ to 5.5xl0³ poise, (III) a weight averaged molecular weight/number averaged molecular weight (M_w/M_n) > 4, and (IV) melt index at 190 degrees Celsius under 2. 16 kg of 0.05 to 4 g/10 min.

[0050] In some embodiments, the method for recycling plastic waste includes the steps of:

(a) collecting the plastic waste from residential, commercial, and industrial sites, wherein the plastic waste is selected from the group consisting of postconsumer recyclate and post-industrial recyclate, and made from or containing a polyolefin and a contaminant;

(b) grinding the plastic waste, thereby providing particles having dimensions smaller than 1000 microns;

(c) characterizing the particles, thereby determining the particles’

(i) viscosity at a shear rate of 0.025 radians/second,

(ii) viscosity at a shear rate of 100 radians/second,

(iii) molecular weight distribution, and

(iv) melt index at 190 degrees Celsius under 2. 16 kg force;

(d) melting the particles, thereby yielding a fusion-melt; and

(e) pelletizing the fusion-melt, thereby forming a pelletized resin selected from the group consisting of a pelletized, post-consumer recycled (PCR) resin and a pelletized, post-industrial recycled (PIR) resin.

[0051] In some embodiments, the method for recycling plastic waste includes the steps of:

(b) grinding the plastic waste, thereby providing particles having dimensions smaller than 1000 microns; (c) characterizing the particles, thereby determining the particles’

(i) viscosity at a shear rate of 0.025 radians/second,

(ii) viscosity at a shear rate of 100 radians/second,

(iii) molecular weight distribution, and

(iv) melt index at 190 degrees Celsius under 2. 16 kg force;

(d) melt blending

(i) a first amount of the particles with

(ii) a second amount of a high molecular weight, high density polyethylene having a melt index of 0.008 to 1.0 g/ 10 min, wherein the first and second amounts are selected based upon the properties determined in characterizing step (c), thereby yielding a fusion-melt having (I) a viscosity at a shear rate of 0.025 radians/second of 8.0* 10⁴ to 1.2* 10⁵ poise, (II) a viscosity at a shear rate of 100 radians/second of 8.8*10³ to 5.5xl0³ poise, (III) a weight averaged molecular weight/number averaged molecular weight (Mw/M_n) > 4, and (IV) melt index at 190 degrees Celsius under 2.16 kg of 0.05 to 4 g/ 10 min; and

(e) pelletizing the fusion-melt, thereby forming a pelletized, machinedirection-oriented, PCR-based film resin.

[0052] In some embodiments, the fusion-melt is made from or containing:

(a) from 5 % by weight to 95 % by weight, based upon the total weight of the polymer composition, of the plastic waste particles; and

(b) from 5 % by weight to 95 % by weight, based upon the total weight of the polymer composition, of the high molecular weight, high density polyethylene.

In some embodiments, the ratio between the components, based upon weight, is 10:90, alternatively 20:80, alternatively 30:70; alternatively 40:60; alternatively 50:50; alternatively 60:40; alternatively 70:30; alternatively 80:20; alternatively 90:10.

[0053] In some embodiments, the method for recycling plastic waste further includes the steps of:

(a.i) sorting the plastic waste; and

(a.ii) cleaning the plastic waste. [0054| In some embodiments, the method for recycling plastic waste further includes the steps of:

(b.i) sieving the plastic waste;

(b.ii) separating the plastic waste by particle size; and

(b.iii) collecting the plastic waste in the form of granules or powders.

[0055] In some embodiments, the method for recycling plastic waste include one or more cleaning steps. As previously noted, the mention of one or more method steps does not preclude the presence of additional method steps before or after the combined recited steps or intervening method steps between those steps expressly identified.

[0056] In some embodiments, the plastic waste is made from or containing automobile parts, bleach bottles, food containers, freezer and shopping bags, milk jugs, outdoor furniture, packaging materials, piping, plastic bottles, playground equipment, shampoo bottles, signage and fixtures, toys, and contaminants. In some embodiments, the contaminants are selected from the group consisting of acrylonitrile butadiene styrene (ABS), calcium carbonate, coffee grounds, diapers, dirt, fillers, food stuffs, glass, grass, labels, metals (including aluminum), nylon, other inorganics, other polymers, paper, plant stems, polycarbonates, polyethylene terephthalate (PET), processing additives, property-imparting additives, rubbers, and wood.

[0057] In some embodiments, the high density polyethylene has a melt index of 0.008 to 1.0 g/ 10 min, alternatively from 0.01 to 0.3 g/10 min, alternatively from 0.0 Ito 0.1 g/10 min. In some embodiments, the high density polyethylene is an ethylene homopolymer or an ethylene copolymer having up to 5 weight percent of a comonomer. In some embodiments, the comonomer is selected from the group consisting of propylene, butene- 1 , and hexene- 1. In some embodiments, the high density polyethylene is Alathon™ L4903 high molecular weight high density ethylene copolymer, which is commercially available from LyondellBasell and has a melt index of 0.027 g/10 min and a density of 0.949 g/cm³.

[0058] In some embodiments, the present disclosure provides a post-consumer recycled resin prepared from a post-consumer recyclate, wherein the resin is selected from the group consisting of polyethylene and polypropylene. In some embodiments, the polyethylene is a high- density polyethylene.

[0059] In some embodiments, the present disclosure provides a post-industrial recycled resin prepared from a post-industrial recyclate, wherein the resin is selected from the group consisting of polyethylene and polypropylene. [0060] In some embodiments, the present disclosure provides a polymer composition made from or containing resin selected from the group consisting of a post-consumer recycled resin and a post-industrial recycled resin. In some embodiments, the polymer composition is made from or containing:

(a) from 5 % by weight to 95 % by weight, based upon the total weight of the polymer composition, of a resin selected from the group consisting of a post-consumer recycled resin and a post-industrial recycled resin; and

(b) from 5 % by weight to 95 % by weight, based upon the total weight of the polymer composition, of a virgin polymer.

[0061] In some embodiments, the resin is selected from the group consisting of HDPE PCR and PP PCR. In some embodiments, the resin is the base resin of the polymer composition. In some embodiments, the resin is a complementary resin. In some embodiments, the resin is a component in an additive composition or a filler, for use with a virgin or other PCR resin. In some embodiments, the resin is used as a filler in amount up to 50 % by weight, alternatively from 0.5 % by weight to 30 % by weight, alternatively from 1.0 % by weight to 20% by weight, based upon the total weight of the polymer composition.

[0062] In some embodiments, the machine-direction-oriented, PCR-based film resin has a viscosity at a shear rate of 0.025 radians/second of 8.0*10⁴ to 1.2*10⁵ poise, alternatively from 8.4*10⁴ to 1.0*10⁵ poise, alternatively from 8.9*10⁴ to 9.4*10⁴ poise.

[0063] In some embodiments, the machine-direction-oriented, PCR-based film resin has a viscosity at a shear rate of 100 radians/second of 8.8*10³ to 5.5xl0³ poise, alternatively 8.4*10³ to 6.7*10³ poise, alternatively from 8.0*10³ to 7.6* 10³ poise.

[0064] In some embodiments, the machine-direction-oriented. PCR-based film resin has a weight averaged molecular weight/number averaged molecular weight (Mw/Mn) > 4, alternatively >5.

[0065] In some embodiments, the machine-direction-oriented, PCR-based film resin has melt index at 190 degrees Celsius under 2.16 kg of 0.05 to 4 g/10 min, alternatively 0.05 to 2.0 g/10 min, alternatively 0.05 to 0.9 g/10 min.

[0066] In some embodiments, the resin bears the International Code Council (ICC) Certification.

[0067] In some embodiments, the the machine-direction-oriented, PCR-based film resin has Food and Drug Administration approval. [0068] In some embodiments, the polymer composition is further made from or containing an additive composition. In some embodiments, the additive composition imparts properties such as thermal stability, light and ultraviolet protection, and color. In some embodiments, the additive composition is present in an amount from 0.05 % by weight to 10 % by weight, alternatively from 0. 1 % by weight to 8 % by weight, based upon the total weight of the polymer composition.

[0069] In some embodiments, the present disclosure provides an article of manufacture made from or containing a resin selected from the group consisting of post-consumer recycled resins and post-industrial recycled resins. In some embodiments, the article of manufacture is selected from the group consisting of blow-molded articles, films, flexibles, injection-molded articles, packaging, and piping. In some embodiments, the article of manufacture is useful in noncosmetic-intensive. post consumer recycled resin applications, including agricultural film and trash bags.

[0070] In some embodiments, the present disclosure provides a machine-direction- oriented film. In some embodiments, a single layer of the film has a thickness of less than 6.0 mil, alternatively from 0.2 mil to 6.0 mil, alternatively from 0.4 mil to 3.0 mil, alternatively from 1.0 mil to 3.0 mil.

Claims

CLAIMS What is claimed is:

1. A method for recycling plastic waste comprising the steps of:

(a) collecting the plastic waste from residential, commercial, and industrial sites, wherein the plastic waste is selected from the group consisting of post-consumer recyclate and post-industrial recyclate, and made from or containing a polyolefin and a contaminant;

(c) characterizing the particles, thereby determining the particles’

(i) viscosity at a shear rate of 0.025 radians/second,

(ii) viscosity at a shear rate of 100 radians/second,

(iii) molecular weight distribution, and

(iv) melt index at 190 degrees Celsius under 2.16 kg force;

2. The method for recycling plastic waste of Claim 1, further comprising the steps of:

(d) melting the particles, thereby yielding a fusion-melt; and

3. The method for recycling plastic waste of Claim 1, further comprising the steps of:

(d) melt blending

(i) a first amount of the particles with

(ii) a second amount of a high molecular weight, high density polyethylene having a melt index of 0.008 to 1.0 g/10 min, wherein the first and second amounts are selected based upon the properties determined in characterizing step (c), thereby yielding a fusion-melt having (I) a viscosity at a shear rate of 0.025 radians/second of 8.0*10⁴ to 1.2*10⁵ poise, (II) a viscosity at a shear rate of 100 radians/second of 8.8*10³ to 5.5xl0³ poise, (III) a weight averaged molecular weight/number averaged molecular weight (Mw/Mn) > 4. and (IV) melt index at 190 degrees Celsius under 2.16 kg of 0.05 to 4 g/ 10 min; and

4. The method for recycling plastic waste of Claim 1, wherein the plastic waste comprises automobile parts, bleach bottles, food containers, freezer and shopping bags, milk jugs, outdoor furniture, packaging materials, piping, plastic bottles, playground equipment, shampoo bottles, signage and fixtures, toys, and contaminants.

5. The method for recycling plastic waste of Claim 4, wherein the contaminants are selected from the group consisting of acrylonitrile butadiene styrene (ABS). calcium carbonate, coffee grounds, diapers, dirt, fillers, food stuffs, glass, grass, labels, metals (including aluminum), nylon, other inorganics, other polymers, paper, plant stems, polycarbonates, polyethylene terephthalate (PET), processing additives, property-imparting additives, rubbers, and wood.

6. A machine-direction-oriented, PCR-based film resin comprising

(a) a post-consumer recycled resin selected from the group consisting of polyethylene and polypropylene and

(b) a high molecular weight, high density polyethylene having a melt index of 0.008 to 1.0 g/ 10 min. having

(I) a viscosity at a shear rate of 0.025 radians/second of 8.0* 10⁴ to 1.2*10⁵ poise,

(II) a viscosity at a shear rate of 100 radians/second of 8.8* 10³ to 5.5xl0³ poise,

(III) a weight averaged molecular weight/number averaged molecular weight (Mw/Mn) > 4, and

(IV) melt index at 190 degrees Celsius under 2. 16 kg of 0.05 to 4 g/10 min.

7. An article of manufacture comprising the post-consumer recycled resin of Claim 6.

8. The article of manufacture of Claim 7, wherein the article is a machine-direction-oriented PCR-based film.